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          <th colspan="3" align="center">DbEnv::mutex_set_init()</th>
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            <h2 class="title" style="clear: both"><a id="mutexset_init"></a>DbEnv::mutex_set_init()</h2>
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      <pre class="programlisting">#include &lt;db_cxx.h&gt;

int
DbEnv::mutex_set_init(u_int32_t init); </pre>
      <p>
        Configure the inital number of mutexes to allocate.
     </p>
      <p>
         Berkeley DB allocates a default number of mutexes based on the
         initial configuration of the database environment.  The
         <code class="methodname">DbEnv::mutex_set_init()</code> method is used to
         override this default number of mutexes to allocate.  This may be done
         to either speed up startup, or to force more work to be done at
         startup to avoid later contention due to allocation.
     </p>
      <p>
         The database environment's inital number of mutexes may also be
         configured using the environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file.  The syntax
         of the entry in that file is a single line with the string
         "mutex_set_init", one or more whitespace characters, and the
         initial number of mutexes. Because the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is read
         when the database environment is opened, it will silently overrule
         configuration done before that time.
     </p>
      <p>
         The <code class="methodname">DbEnv::mutex_set_init()</code> method
         configures a database environment, not only operations performed
         using the specified <a class="link" href="env.html" title="Chapter 5.  The DbEnv Handle">DbEnv</a>
         handle.
     </p>
      <p>
         The <code class="methodname">DbEnv::mutex_set_init()</code> method may not
         be called after the 
         <a class="xref" href="envopen.html" title="DbEnv::open()">DbEnv::open()</a>  method is
         called.  If the database environment already exists when 
         <a class="xref" href="envopen.html" title="DbEnv::open()">DbEnv::open()</a>  is called, the
         information specified to
         <code class="methodname">DbEnv::mutex_set_init()</code> will be ignored.
     </p>
      <p>
         The <code class="methodname">DbEnv::mutex_set_init()</code> <span>
            
            <span>
                method either returns a non-zero error value or throws an
                exception that encapsulates a non-zero error value on
                failure, and returns 0 on success.
            </span>
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      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="idp9229200"></a>Parameters</h3>
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                <h4 class="title"><a id="idp9228552"></a>init</h4>
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          <p>
                  The <span class="bold"><strong>init</strong></span> parameter is the absolute
                  number of mutexes to allocate.
             </p>
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      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="idp9217608"></a>Errors</h3>
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        <p>
             The <code class="methodname">DbEnv::mutex_set_init()</code> <span>
            
            <span>
                method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a> 
                exception, encapsulating one of the following non-zero errors, or return one
                of the following non-zero errors:
            </span>
        </span>
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                <h4 class="title"><a id="idp9237912"></a>EINVAL</h4>
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                An invalid flag value or parameter was specified.
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              <h3 class="title"><a id="idp9236616"></a>Class</h3>
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        <p>
            <a class="link" href="env.html" title="Chapter 5.  The DbEnv Handle">DbEnv</a>  
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              <h3 class="title"><a id="idp9231648"></a>See Also</h3>
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        <p>
                 <a class="xref" href="mutex.html#mutexlist" title="Mutex Methods">Mutex Methods</a> 
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